#At file:///home/kgeorge/mysql/work/B45828-5.1-bugteam/ based on revid:v.narayanan@stripped
3017 Georgi Kodinov 2009-07-07
Bug #36259 (Optimizing with ORDER BY) and bug#45828 (Optimizer won't
use partial primary key if another index can prevent filesort
The fix for bug #28404 causes the covering ordering indexes to be
preferred unconditionally over non-covering and ref indexes.
Fixed by comparing the cost of using a covering index to the cost of
using a ref index even for covering ordering indexes.
Added an assertion to clarify the condition the local variables should
be in.
@ mysql-test/include/mix1.inc
Bug #36259: fixed a non-stable test case
@ mysql-test/r/innodb_mysql.result
Bug #36259 and #45828 : test case
@ mysql-test/t/innodb_mysql.test
Bug #36259 and #45828 : test case
@ sql/sql_select.cc
Bug #36259 and #45828 : don't consider covering indexes supperior to
ref keys.
modified:
mysql-test/include/mix1.inc
mysql-test/r/innodb_mysql.result
mysql-test/t/innodb_mysql.test
sql/sql_select.cc
=== modified file 'mysql-test/include/mix1.inc'
--- a/mysql-test/include/mix1.inc 2009-06-15 15:57:06 +0000
+++ b/mysql-test/include/mix1.inc 2009-07-07 12:52:34 +0000
@@ -1498,9 +1498,9 @@ INSERT INTO t1 VALUES
(4,1,3,'pk',NULL),(5,1,3,'c2',NULL),
(2,1,4,'c_extra',NULL),(3,1,4,'c_extra',NULL);
-EXPLAIN SELECT * FROM t1 WHERE tid = 1 AND vid = 3 ORDER BY idx DESC;
+EXPLAIN SELECT * FROM t1 FORCE INDEX (PRIMARY) WHERE tid = 1 AND vid = 3 ORDER BY idx DESC;
-SELECT * FROM t1 WHERE tid = 1 AND vid = 3 ORDER BY idx DESC;
+SELECT * FROM t1 FORCE INDEX (PRIMARY) WHERE tid = 1 AND vid = 3 ORDER BY idx DESC;
DROP TABLE t1;
=== modified file 'mysql-test/r/innodb_mysql.result'
--- a/mysql-test/r/innodb_mysql.result 2009-06-15 15:57:06 +0000
+++ b/mysql-test/r/innodb_mysql.result 2009-07-07 12:52:34 +0000
@@ -1701,10 +1701,10 @@ INSERT INTO t1 VALUES
(4,1,2,'c2',NULL),(5,1,2,'c1',NULL),(2,1,3,'c2',NULL),(3,1,3,'c2',NULL),
(4,1,3,'pk',NULL),(5,1,3,'c2',NULL),
(2,1,4,'c_extra',NULL),(3,1,4,'c_extra',NULL);
-EXPLAIN SELECT * FROM t1 WHERE tid = 1 AND vid = 3 ORDER BY idx DESC;
+EXPLAIN SELECT * FROM t1 FORCE INDEX (PRIMARY) WHERE tid = 1 AND vid = 3 ORDER BY idx DESC;
id select_type table type possible_keys key key_len ref rows Extra
-1 SIMPLE t1 index vid PRIMARY 12 NULL 16 Using where
-SELECT * FROM t1 WHERE tid = 1 AND vid = 3 ORDER BY idx DESC;
+1 SIMPLE t1 index NULL PRIMARY 12 NULL 16 Using where
+SELECT * FROM t1 FORCE INDEX (PRIMARY) WHERE tid = 1 AND vid = 3 ORDER BY idx DESC;
vid tid idx name type
3 1 4 c_extra NULL
3 1 3 c2 NULL
@@ -2137,4 +2137,75 @@ GROUP BY t1.b;
a b c d a b e a b
1 1 1 0 1 1 2 1 1
DROP TABLE t1, t2, t3;
+#
+# Bug #45828: Optimizer won't use partial primary key if another
+# index can prevent filesort
+#
+CREATE TABLE `t1` (
+c1 int NOT NULL,
+c2 int NOT NULL,
+c3 int NOT NULL,
+PRIMARY KEY (c1,c2),
+KEY (c3)
+) ENGINE=InnoDB;
+INSERT INTO t1 VALUES (5,2,1246276747);
+INSERT INTO t1 VALUES (2,1,1246281721);
+INSERT INTO t1 VALUES (7,3,1246281756);
+INSERT INTO t1 VALUES (4,2,1246282139);
+INSERT INTO t1 VALUES (3,1,1246282230);
+INSERT INTO t1 VALUES (1,0,1246282712);
+INSERT INTO t1 VALUES (8,3,1246282765);
+INSERT INTO t1 SELECT c1+10,c2+10,c3+10 FROM t1;
+INSERT INTO t1 SELECT c1+100,c2+100,c3+100 from t1;
+INSERT INTO t1 SELECT c1+1000,c2+1000,c3+1000 from t1;
+INSERT INTO t1 SELECT c1+10000,c2+10000,c3+10000 from t1;
+INSERT INTO t1 SELECT c1+100000,c2+100000,c3+100000 from t1;
+INSERT INTO t1 SELECT c1+1000000,c2+1000000,c3+1000000 from t1;
+SELECT * FROM t1 WHERE c1 = 99999999 AND c3 > 1 ORDER BY c3;
+c1 c2 c3
+EXPLAIN SELECT * FROM t1 WHERE c1 = 99999999 AND c3 > 1 ORDER BY c3;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ref PRIMARY,c3 PRIMARY 4 const 1 Using where; Using filesort
+EXPLAIN SELECT * FROM t1 FORCE INDEX (PRIMARY) WHERE c1 = 99999999 AND c3 > 1 ORDER BY c3;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ref PRIMARY PRIMARY 4 const 1 Using where; Using filesort
+CREATE TABLE t2 (
+c1 int NOT NULL,
+c2 int NOT NULL,
+c3 int NOT NULL,
+KEY (c1,c2),
+KEY (c3)
+) ENGINE=InnoDB;
+explain SELECT * FROM t2 WHERE c1 = 99999999 AND c3 > 1 ORDER BY c3;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t2 ref c1,c3 c1 4 const 1 Using where; Using filesort
+DROP TABLE t1,t2;
+#
+# 36259: Optimizing with ORDER BY
+#
+CREATE TABLE t1 (
+a INT NOT NULL AUTO_INCREMENT,
+b INT NOT NULL,
+c INT NOT NULL,
+d VARCHAR(5),
+e INT NOT NULL,
+PRIMARY KEY (a), KEY i2 (b,c,d)
+) ENGINE=InnoDB;
+INSERT INTO t1 (b,c,d,e) VALUES (1,1,'a',1), (2,2,'b',2);
+INSERT INTO t1 (b,c,d,e) SELECT RAND()*10000, RAND()*10000, d, e FROM t1;
+INSERT INTO t1 (b,c,d,e) SELECT RAND()*10000, RAND()*10000, d, e FROM t1;
+INSERT INTO t1 (b,c,d,e) SELECT RAND()*10000, RAND()*10000, d, e FROM t1;
+INSERT INTO t1 (b,c,d,e) SELECT RAND()*10000, RAND()*10000, d, e FROM t1;
+INSERT INTO t1 (b,c,d,e) SELECT RAND()*10000, RAND()*10000, d, e FROM t1;
+INSERT INTO t1 (b,c,d,e) SELECT RAND()*10000, RAND()*10000, d, e FROM t1;
+EXPLAIN SELECT * FROM t1 WHERE b=1 AND c=1 ORDER BY a;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ref i2 i2 8 const,const 1 Using where; Using filesort
+EXPLAIN SELECT * FROM t1 FORCE INDEX(i2) WHERE b=1 and c=1 ORDER BY a;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 ref i2 i2 8 const,const 1 Using where; Using filesort
+EXPLAIN SELECT * FROM t1 FORCE INDEX(PRIMARY) WHERE b=1 AND c=1 ORDER BY a;
+id select_type table type possible_keys key key_len ref rows Extra
+1 SIMPLE t1 index NULL PRIMARY 4 NULL 128 Using where
+DROP TABLE t1;
End of 5.1 tests
=== modified file 'mysql-test/t/innodb_mysql.test'
--- a/mysql-test/t/innodb_mysql.test 2009-06-07 20:40:53 +0000
+++ b/mysql-test/t/innodb_mysql.test 2009-07-07 12:52:34 +0000
@@ -380,4 +380,85 @@ SELECT * FROM t1, t2, t3
DROP TABLE t1, t2, t3;
+--echo #
+--echo # Bug #45828: Optimizer won't use partial primary key if another
+--echo # index can prevent filesort
+--echo #
+
+# Create the table
+CREATE TABLE `t1` (
+ c1 int NOT NULL,
+ c2 int NOT NULL,
+ c3 int NOT NULL,
+ PRIMARY KEY (c1,c2),
+ KEY (c3)
+) ENGINE=InnoDB;
+
+# populate with data
+INSERT INTO t1 VALUES (5,2,1246276747);
+INSERT INTO t1 VALUES (2,1,1246281721);
+INSERT INTO t1 VALUES (7,3,1246281756);
+INSERT INTO t1 VALUES (4,2,1246282139);
+INSERT INTO t1 VALUES (3,1,1246282230);
+INSERT INTO t1 VALUES (1,0,1246282712);
+INSERT INTO t1 VALUES (8,3,1246282765);
+INSERT INTO t1 SELECT c1+10,c2+10,c3+10 FROM t1;
+INSERT INTO t1 SELECT c1+100,c2+100,c3+100 from t1;
+INSERT INTO t1 SELECT c1+1000,c2+1000,c3+1000 from t1;
+INSERT INTO t1 SELECT c1+10000,c2+10000,c3+10000 from t1;
+INSERT INTO t1 SELECT c1+100000,c2+100000,c3+100000 from t1;
+INSERT INTO t1 SELECT c1+1000000,c2+1000000,c3+1000000 from t1;
+
+# query and no rows will match the c1 condition, whereas all will match c3
+SELECT * FROM t1 WHERE c1 = 99999999 AND c3 > 1 ORDER BY c3;
+
+# SHOULD use the pk.
+# index on c3 will be used instead of primary key
+EXPLAIN SELECT * FROM t1 WHERE c1 = 99999999 AND c3 > 1 ORDER BY c3;
+
+# if we force the primary key, we can see the estimate is 1
+EXPLAIN SELECT * FROM t1 FORCE INDEX (PRIMARY) WHERE c1 = 99999999 AND c3 > 1 ORDER BY c3;
+
+
+CREATE TABLE t2 (
+ c1 int NOT NULL,
+ c2 int NOT NULL,
+ c3 int NOT NULL,
+ KEY (c1,c2),
+ KEY (c3)
+) ENGINE=InnoDB;
+
+# SHOULD use the pk.
+# if we switch it from a primary key to a regular index, it works correctly as well
+explain SELECT * FROM t2 WHERE c1 = 99999999 AND c3 > 1 ORDER BY c3;
+
+DROP TABLE t1,t2;
+
+
+--echo #
+--echo # 36259: Optimizing with ORDER BY
+--echo #
+
+CREATE TABLE t1 (
+ a INT NOT NULL AUTO_INCREMENT,
+ b INT NOT NULL,
+ c INT NOT NULL,
+ d VARCHAR(5),
+ e INT NOT NULL,
+ PRIMARY KEY (a), KEY i2 (b,c,d)
+) ENGINE=InnoDB;
+
+INSERT INTO t1 (b,c,d,e) VALUES (1,1,'a',1), (2,2,'b',2);
+INSERT INTO t1 (b,c,d,e) SELECT RAND()*10000, RAND()*10000, d, e FROM t1;
+INSERT INTO t1 (b,c,d,e) SELECT RAND()*10000, RAND()*10000, d, e FROM t1;
+INSERT INTO t1 (b,c,d,e) SELECT RAND()*10000, RAND()*10000, d, e FROM t1;
+INSERT INTO t1 (b,c,d,e) SELECT RAND()*10000, RAND()*10000, d, e FROM t1;
+INSERT INTO t1 (b,c,d,e) SELECT RAND()*10000, RAND()*10000, d, e FROM t1;
+INSERT INTO t1 (b,c,d,e) SELECT RAND()*10000, RAND()*10000, d, e FROM t1;
+EXPLAIN SELECT * FROM t1 WHERE b=1 AND c=1 ORDER BY a;
+EXPLAIN SELECT * FROM t1 FORCE INDEX(i2) WHERE b=1 and c=1 ORDER BY a;
+EXPLAIN SELECT * FROM t1 FORCE INDEX(PRIMARY) WHERE b=1 AND c=1 ORDER BY a;
+
+DROP TABLE t1;
+
--echo End of 5.1 tests
=== modified file 'sql/sql_select.cc'
--- a/sql/sql_select.cc 2009-07-03 10:43:54 +0000
+++ b/sql/sql_select.cc 2009-07-07 12:52:34 +0000
@@ -13132,9 +13132,17 @@ test_if_skip_sort_order(JOIN_TAB *tab,OR
for (nr=0; nr < table->s->keys ; nr++)
{
int direction;
+
if (keys.is_set(nr) &&
(direction= test_if_order_by_key(order, table, nr, &used_key_parts)))
{
+ /*
+ At this point we are sure that ref_key is a non-ordering
+ key (where "ordering key" is a key that will return rows
+ in the order required by ORDER BY).
+ */
+ DBUG_ASSERT (ref_key != (int) nr);
+
bool is_covering= table->covering_keys.is_set(nr) ||
(nr == table->s->primary_key &&
table->file->primary_key_is_clustered());
@@ -13215,7 +13223,7 @@ test_if_skip_sort_order(JOIN_TAB *tab,OR
*/
index_scan_time= select_limit/rec_per_key *
min(rec_per_key, table->file->scan_time());
- if (is_covering ||
+ if ((ref_key < 0 && is_covering) ||
(ref_key < 0 && (group || table->force_index)) ||
index_scan_time < read_time)
{
Attachment: [text/bzr-bundle] bzr/joro@sun.com-20090707125234-fe4my9xoq1fk7xj2.bundle
| Thread |
|---|
| • bzr commit into mysql-5.1-bugteam branch (joro:3017) Bug#36259 Bug#45828 | Georgi Kodinov | 9 Jul |
